Radio frequency coil and apparatus

Abstract

A radio frequency (RF) coil for a magnetic resonance imaging (MRI) system includes a first end ring, a second end ring, and a plurality of rungs electrically coupled between the first and second end rings, each rung including a first rung portion formed from a plurality of conductors and a second rung portion formed from a single solid conductor. A resonance assembly for a magnetic resonance imaging (MRI) system and an MRI imaging system are also described herein.

What is claimed is: 
     
       1. A radio frequency (RF) coil for a magnetic resonance imaging (MRI) system, the RF coil comprising:
 a first end ring; 
 a second end ring; and 
 a plurality of rungs electrically coupled between the first and second end rings, each rung including a first rung portion and a second rung portion, the first rung portion comprising a multi-conductor assembly including plural wire conductors, the wire conductors individually encased along a length by a first portion of electrical insulation material wherein the wire conductors are electrically insulated from each other, the second rung portion formed from a single solid conductor and coupled in electrical series with the first rung portion; 
 wherein each rung further comprises a third rung portion formed from a plurality of wire conductors, the second rung portion being coupled in electrical series between the first and third rung portions, the wire conductors of the third rung portion individually encased along a length by a second portion of electrical insulation material wherein the wire conductors are electrically insulated from each other. 
 
     
     
       2. The RF coil of  claim 1  wherein the wire conductors of the multi-conductor assembly of the first rung portion are braided together to form the first rung portion. 
     
     
       3. The RF coil of  claim 1  wherein the first rung portion comprises plural wire bundles braided together, each wire bundle formed from a bundled group of wire conductors of the multi-conductor assembly. 
     
     
       4. The RF coil of  claim 1  wherein a group of the wire conductors of the multi-conductor assembly are braided together to form a wire bundle, a plurality of wire bundles being braided together to form the first rung portion. 
     
     
       5. The RF coil of  claim 1  wherein the wire conductors each have a circular cross sectional profile. 
     
     
       6. The RF coil of  claim 1  wherein each of the wire conductors has an outer diameter that is selected based on a desired Radio Frequency (RF) coil operational frequency. 
     
     
       7. The RF coil of  claim 1  wherein the first end ring, the second end ring, and the plurality of rungs are coupled together to form a birdcage coil. 
     
     
       8. The RF coil of  claim 1  wherein the RF coil is at least one of a Transverse Electromagnetic (TEM) coil, a whole body coil, or a local coil. 
     
     
       9. The RF coil of  claim 1  wherein each rung further comprises a first opening located in proximity to the first end ring and a second opening located in proximity to the second end ring. 
     
     
       10. The RF coil of  claim 1  wherein the first rung portion includes an outer insulation layer to encase the wire conductors and maintain the wire conductors in a fixed position with respect to each other. 
     
     
       11. The RF coil of  claim 1  wherein the wire conductors are coupled together to form a ribbon cable. 
     
     
       12. The RF coil of  claim 1  wherein at least one of a quantity or a length of the wire conductors is selected based on an operating frequency of the RF coil. 
     
     
       13. A radio frequency (RF) coil for a magnetic resonance imaging (MRI) system, the RF coil comprising:
 a first end ring; 
 a second end ring; and 
 a plurality of rungs electrically coupled between the first and second end rings, at least one of the rungs including a multi-conductor assembly and a solid conductor coupled in series to the multi-conductor assembly, the multi-conductor assembly partially extending along a length of the rung, the multi-conductor assembly including a plurality of insulated conductors that are braided together to form the multi-conductor assembly, the insulated conductors individually encased along a length by a first portion of electrical insulation material wherein the insulated conductors are electrically insulated from each other; 
 wherein at least one of the rungs further comprises a second multi-conductor assembly that is coupled in series with the solid conductor, the second multi-conductor assembly including a plurality of insulated conductors individually encased along a length by a second portion of electrical insulation material that are braided together to form the second multi-conductor assembly, the solid conductor being coupled between the multi-conductor assemblies. 
 
     
     
       14. The RF coil of  claim 13  wherein each of the plurality of insulated conductors has an outer diameter that is selected based on a desired RF coil operational frequency. 
     
     
       15. The RF coil of  claim 13  wherein the plurality of insulated conductors are braided together to form a wire bundle, a plurality of wire bundles being braided together to form the multi-conductor assembly. 
     
     
       16. The RF coil of  claim 13  wherein each rung further comprises a first opening located in proximity to the first end ring and a second opening located in proximity to the second end ring. 
     
     
       17. A magnetic resonance imaging (MRI) system comprising:
 a superconducting magnet installed in a cryostat; 
 a gradient coil assembly disposed within an inner diameter of the superconducting magnet; and 
 a radio frequency (RF) coil disposed within an inner diameter of the gradient coil assembly, the RF coil comprising: 
 a first end ring; 
 a second end ring; and 
 a plurality of rungs electrically coupled between the first and second end rings, each rung including a first rung portion formed from a first plurality of insulated conductors, a second rung portion formed from a single solid conductor, and a third rung portion formed from a second plurality of insulated conductors, the second rung portion coupled in series between the first and third rung portions, wherein the first plurality and second plurality of insulated conductors each include a group of wire conductors that are individually encased along a length by an electrical insulation material. 
 
     
     
       18. The MRI system of  claim 17  wherein the wire conductors of at least one of the first and second plurality of insulated conductors are braided together. 
     
     
       19. The MRI system of  claim 17  wherein the plurality of insulated conductors forming the first and third portions are positioned parallel to one another, each of the plurality of insulated conductors having a circular cross sectional profile. 
     
     
       20. The MRI system of  claim 17  wherein the first end ring, the second end ring, and the plurality of rungs are coupled together to form a birdcage coil.